<!DOCTYPE html> <html> <body> <audio controls onloadeddata="myFunction()"> <source src="/static/demo/video/horse.ogg" type="audio/ogg"> <source src="/static/demo/video/horse.mp3" type="audio/mpeg"> Your browser does not support the audio element. </audio> <script> function myFunction() { alert("Browser has loaded the current frame"); } </script> </body> </html>